daniel dias SOFTWARE DEVELOPER

Software · systems · products

I build software from start to finish

I turn ideas into complete web applications, from the interface and backend to testing, deployment and the decisions that keep them reliable.

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Open to software roles & freelance projects github linkedin
.NET ASP.NET Core Angular React TypeScript SQL PostgreSQL Docker Azure

Focus

What I do well

Four areas I work in every day, and what each one means in practice.

Backend APIs

REST APIs with clear contracts, validation, authentication and maintainable application flows.

Database design

Relational modelling, Entity Framework Core, SQL Server, PostgreSQL and data consistency.

System design

Exploring caching, service boundaries and infrastructure trade-offs through working projects.

Testing and delivery

Automated tests, Docker, CI/CD and cloud services that move projects beyond local development.

Selected projects

Projects

Some of the projects I've built, with the problem each one solves and how I solved it.

live product
mt

Maltese Transcriber

Real-time transcription product combining ASP.NET Core, SignalR and speech recognition in one focused workflow.

Result

A public product deployed for real use with email delivery, anti-abuse controls, observability, and more than 230 automated tests.

React · .NET 10 · SignalR · Speechmatics Open product
live technical demo

Sports Betting API

A betting platform API built around authentication, wallet consistency and production-minded delivery.

Result

A public Swagger demo deployed to Azure Container Apps with automated tests covering the core betting and wallet behaviour.

.NET 9 · EF Core · Azure Container Apps Open demo
engineering project
pm

PayMaestro

Payment orchestration shaped around idempotency, fraud checks, cascade routing and an auditable state machine.

Result

A spec-first backend that demonstrates deterministic orchestration, traceable decisions, and controlled recovery from provider failure.

.NET · payments · idempotency · fraud rules View source
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Posts

Blog

Notes about .NET, databases, testing and the engineering decisions behind working software.

5 min read Preventing Inconsistent Data with ACID Transactions #Databases Every ACID property has a default, and three of them promise less than the word does. The fourth default is honest, which turns out to be the dangerous part. 5 min read Pix: How Brazil's Instant Payment System Works #Payments Pix isn't an app and isn't a company. It's a payment system the central bank built and operates itself, which is exactly the part that confuses people outside Brazil. 5 min read How .NET Modernization Works with the Copilot Upgrade Agent #.NET Microsoft published a free course on upgrading .NET Framework apps to .NET 10, plus full docs on the Copilot modernization agent. Here's what the assess, plan, execute workflow actually does. 3 min read The YouTube Channels Helping Me Learn C# and .NET #.NET Tim Corey for fundamentals that actually stick, Nick Chapsas for what changed in the latest versions, and Balta plus Canal .NET in Portuguese. Four channels doing four different jobs. 3 min read Building a Simple Fraud-Detection Rule in .NET #.NET A walkthrough of one real fraud rule: the interface, the verdict type, the repository query behind it, and why the whole thing is about 20 lines of actual logic. 3 min read How I'm Learning System Design #System Design Most system design content assumes you have already run something in production. Building what the videos explain, instead of only watching them, closes that gap faster than waiting for the experience to arrive.
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Tell me what you're building, what already exists and where you need help.

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